The baby name Letha appears in baby name data for the United States from 1910 to 1983. It was most popular in 1916 with 635 babies given the name.
In the later years of this period, Letha has become less common than it once was.
| Year | Count |
|---|---|
| 1910 | 286 |
| 1911 | 309 |
| 1912 | 321 |
| 1913 | 408 |
| 1914 | 434 |
| 1915 | 585 |
| 1916 | 635 |
| 1917 | 589 |
| 1918 | 633 |
| 1919 | 569 |
| 1920 | 531 |
| 1921 | 537 |
| 1922 | 482 |
| 1923 | 450 |
| 1924 | 459 |
| 1925 | 555 |
| 1926 | 542 |
| 1927 | 495 |
| 1928 | 460 |
| 1929 | 440 |
| 1930 | 444 |
| 1931 | 330 |
| 1932 | 345 |
| 1933 | 316 |
| 1934 | 298 |
| 1935 | 290 |
| 1936 | 264 |
| 1937 | 264 |
| 1938 | 226 |
| 1939 | 201 |
| 1940 | 181 |
| 1941 | 181 |
| 1942 | 142 |
| 1943 | 189 |
| 1944 | 148 |
| 1945 | 137 |
| 1946 | 109 |
| 1947 | 202 |
| 1948 | 132 |
| 1949 | 123 |
| 1950 | 169 |
| 1951 | 79 |
| 1952 | 109 |
| 1953 | 144 |
| 1954 | 165 |
| 1955 | 159 |
| 1956 | 220 |
| 1957 | 142 |
| 1958 | 163 |
| 1959 | 230 |
| 1960 | 176 |
| 1961 | 150 |
| 1962 | 183 |
| 1963 | 174 |
| 1964 | 158 |
| 1965 | 192 |
| 1966 | 199 |
| 1967 | 146 |
| 1968 | 58 |
| 1969 | 73 |
| 1970 | 66 |
| 1971 | 52 |
| 1972 | 29 |
| 1973 | 46 |
| 1974 | 19 |
| 1975 | 8 |
| 1976 | 8 |
| 1977 | 14 |
| 1978 | 18 |
| 1979 | 11 |
| 1981 | 6 |
| 1983 | 5 |